Endless belt conveyer drive



Nov. 7, 195o R DALE 2,528,865

ENDI-ESS BELT CONVEYER DRIVE Filed May 5. 1947 ATTORNEY.

Patented Nov. 7, v195() .ENDLEss BELT coNvEYEn DRIVE l Il, I ,George R. Dale, Los Angeles, Calif.

, 'Appiieatipn May 5, 1947,seria1`Np'. 745,915

l This invention relates toa-drive vfor an endless belt and to a .conveyonunit'employing such abelt drive.

' The presentbelt drive:Y is vparticularly adapted for use. with live rollers .conveyors,v that is, conveyors wherein the moved article is propelled by the positive movement of rollers over which it passes. These may be contrasted with .gravity roller conveyors wherein gravity is the vforce activating the moved article and the rollers over which it passes are turned only by its passage, thus acting merely as passive roller bearings.

vIn live roller conveyors, the rollers may be actuated by a chain drive,or as in the present illustration, by a frictional belt drive. In current practice, various means are employed to keep the endless belt taut, such as mounting a weighted roller to press it outward at a designated point so as to take up slack. "This is a considerable problem since the amount of slack in a line is l' constantly changing; for example, a' leather belt will expand and contract with changes of atmospheric moisture content.

Accordingly, it is an object of the present invention to provide a belt drive which may be used with complete indifference to the amount of slack in the belt, and without making any compensation for the same.

Another purpose is the provision of tensioning means in said drive which serves to adjust the same for different belt thicknesses.

Other objects and advantages of the invention, now reduced to practice, will be apparent from the'following description and claims, the novelty consisting in the features of' construction, combination'of parts, the'xunique. relations' of the members and the relative. proportioning'disposition, and operation thereof, al1V as more completely. outlined herein and. particularlypointed out in the appended claims. y

In the drawings, which form part of the present specication:

Fig. l is a sideelevational view of a live roller conveyor embodying my invention,l as seen along thelirle |,-l OFgz. 2.

Fig.` v2. is f Ta fragmentary. ,transverse sectional view' omitting the' upperrollers taken through the conveyorralong thel ine.,2f2 of Fig. 1.

Fig, 3 is an enlarged side elevational view, with parts broken away, of the pair of belt-driving rollers.

A4 is a viewr corresponding Yto Fig. V13 and showing a modiedmourltng of the driving rollers wherein a resilienttens ioningl oi-the-beltis claimsf (o1. 19a- 203) In the embodiment of the invention here illustrated, there is shown an enlarged, generally reotangularr frame I0 mounted on suitable upright supporting legs I2, i4 and I6, L-shaped in cross section; and reinforced by angularly attached cross braceslil and 20. .j

A pair of horizontal, fiatsupporting rails or slats 22 .and 24 are. disposed along the opposite sidesfof the frame and have secured to their upper and lower faces respectively, as by bolts 26, outwardly opening angle irons or brackets of which the upper pair 28 and 30 are L-shaped with their bolted footing portions 28a and 30a extending outward and their upright portions 2,81) and 30h disposed parallel to each other so as to form a channel or guideway, and supporting jointly therebetween two series of transversely mounted, horizontal rollers 32 and 33, the one series vertically spaced above the other with their several axles34 journaled in corresponding apertures in the sides 28h and 30h of the guideway and secured therein by nuts 36 threadedly mounted on their outer ends.

' The downwardly extending brackets 33 and `l0 are shaped similarA to the L-members 28 and 30 above except for an intermediate section of each one which is cup shaped, presenting a generally Ujsectionwhen cutl either vertically or horizontally, as seen particularly in Fig. 2. These outwardly opening, housing cups have their top arms 38a and 40a bolted along the bottom of the side rails 22. and 2li,V and their inner, downwardly extending portions 38b and 4Gb each provided with a pair of longitudinal slots 42 (Fig. 3). l Each housingcup 38 and 4U is provided with end walls 4d and 46 vand with a horizontal partie tion 48 spaced below the top thereof by vertical strutsy 50 and 52, Slidably mounted within the cup below vthe partition 48 are a pair of bearing blocks v54 and 56, each centrally apertured to receive therethrough the axle shaft 58 or 6l! of a roller 62 'or 64 which pair of rollers are laterally spacedgapart Vand suspended between the oppoe site housing cups with their shafts projecting through the slots 42 therein. On the outer ends of each axle, beyond the sliding blocks 54, 56, an annular collar 66 is mounted thereon by a radial sety screw 68 traversing the collar and seating against'the shaft.' 5

These two rollers 62 and 54 each have a metal disk 1Q fixed to each end of their body portion and formed of greater diameter than the height of theadjacent slots 42, so as to form a protecf tive guard or bearing surface in the event of sliding-iepgagement .with the adjacent inner-- cup face 38h or @6b. In contrast, the outer peripheral portions l2 of the rollers are formed of cork, rubber or other material adapted to frictionally engage an endless belt I4 disposed between the pair of laterally spaced rollers 62 and 64 which are thus arranged to press against the belt from either side, as will shortly be evident.

One ofthis pair of rollers is a driving roller (64) and for this purpose is provided with an outer sprocket 'E6 which is engaged by a link pulley '18. 'Ihe pulley is operated by suitable means such as a motor 80 mounted on an autore wardly projecting, horizontal extension B2 of the side rail 22. The other roller (62) is an idler. Each end wall 44 and 46 of the opposite cup housing 38 and 4B is provided with a `tapped aperture 84 and 86 through which is lthreadedly inserted an adjusting screw `88 and 96, re-

the drilled opening l 60 of the sliding plate. rdl- 'are threadedly inserted through the end housing '46'aand bear against the outer face of the slidingr plate 98.y By this construction, it will be seen, the resilient tension of the spring |06 is imposed on the movable bearing block 56a and the amount spectively, which bears against the center of ltlie outer face of the sliding bearing block 54 or 56, whereby the lateral displacement Yof the two rollers 62 and 64 from each other may be regulated by movement of their'mounting blocks. Thus, by tightening up these screws, the grip of the two rollers on the belt can be increased to compensate for wear or shrinkage or to overcome slipping of the belt.

The endless belt 14, which is thus drawn be- `tween the engaging rollers 62 and 64 is pulled, in turn, over a lower idler roller 92 and lan enlarged end roller 94, and then betweenthe two "series of live rollers 32 and 33 which are spaced apart by the thickness of the belt and accordingly are both rotated by movement of the belt. It is thus evident that a carton or other :article placed upon the carrying rollers 32 will be conveyed along the guideway to one end or the other, depending upon which direction 'the belt is moved.

It will be apparent, of course, that either or both of the roller series 32 and 33 could be elimif1 nated and the article moved, for eX'ample,by the belt directly, either with an'idler rsupporting rollrer (33) or not; or the carrying rollers I32 could be used with the belt in the absence of the supporting rollers. In the present illustration, the supporting rollers 33 are employed principallyfto maintain the belt taut against the upper' carry- -ing rollers.

At the opposite endof the channel the belt passes over another enlarged end'rollerf96 and then underneath the frame to return to the ipair of actuating rollers '62 and 64. It will be noted in this connection, that slack in the belt'will ac, cumulate along the outlet side of the twodrive rollers, being draped over 92a and 92h, while the belt moving along the top of the channel is kept taut by the pull of the pair of actuating rollers (i2, 64. Thus no precautions need be resorted to, as in prior constructions, to prevent or compensate for slackness in the belt, the only a'd'- justment required being that ofY maintaining the tension between the pair of 'driving pulleys vby means of the screws 88 and 90.

A modied form of tensioning adjustmentof l the two rollers 62, 64 is shown in Figfl wherein the bearing blocks 54a, and the bearing vblocks 56a are slidable as before. Also slidablyV mounted in the housing, between the adjustablebearing block 56a and the adjacent housingend "4`6a1`is a vertical plate 98, disposedparallel vto the block and having a central vopeningllll) drilled-therethrough. An adjustable stop screw '|62 yis thread'- edly mounted in a tapped aperture l'04 fo'f the housing end 46a and then freely inserted-through of resilience is 'further regulated by adjustment of the sliding plate 98 by the two positioning screws |68 and H0.

While Ivhave-'shown'and described infsome detail a*presentlypreferred'embodiment of my end; less belt drive, it is to be understood `that various =niodication`s may be made in the construction and operation thereof within the scope 4of the subsequently claimed 'invention which is to be 'eonstrued broadly and ylimited only 'by the prior art.

- I claim: n

v1. Alive roller conveyorlincluding incombination: ay supporting frame fha-ving an elongated guideway `f'orrned therein; y-a vseries -of rollers transversely ymounted along said `guideway; an endless `belt adapted to yactuate s'aid rollers by frictional'engagemeht therewith; 'a tpai-r of roll/- ers laterally spaced apart'onroppo'site sides of saidbelt so asto frictionally engag'eit therebetween/at leas'tone of said-pair of Arollers rhaving an yaxle projecting ffr'om each end and -inserted through a longitudinalslot-formed'in each -side of said Trame; 'anfopposing pairfof 'reciprocable bearing blocks apertured lto receive the endsof said axle therein; an adjustable stop screw'disposedf'attimes to 'bearfiagainsteach lof said-bearingblocks whereby thespacing of saidrblocksiand their rollerfrom v1thefadjacent 'rolleriofsaid pair is limited; driving means operatively connected to one of said pair of rollers, anaperturedfplate spaced-from`each "of saidblo'cks' and freely slidable over fits-respective r'egu-lating screw, Ya coil spring circumposedon-each'of said screws and bearing `respectively against 'said 'fblock and nits adjacent plate,l and therfadjusting means adapted to1regulate the displacement of each of said plates from its adjacent block.

2. A live roller conveyorfincluding lncombination: a supporting 'housing having 'an elongated guideway `formed therein; a series "of rollers transversely vmounted faiong vsaid gui'deway; an endless belt adapted to actuatesaidrollersby frictional engagement therewith; ja pair of rollers laterally spaced apart on opposite sides v=oi said'beltso as to frictl'ona'llyengage itthereb'etween drivingA 'means foperatively connected "to one o f said pair of rollers; iadjistable tension"- ing means adapted `roregulate .fthe displacement of "said "rollers fron'feachother, whereby belts of diierent'thicknes'slmaybe frio'ved" by -thedrivf ing Amemberfof saidpairlbf rollersfsaii' adjustable tensioning means vfcompris-ir'ig "ya pair vfo'f "recipro-v cable imounting blocks suspending one of sai-zlllller'sbe'tween A"themfa fslidable plate spaced a art from eaehbffsaid elders-guide 'rrias'fdr d ent spring means disposed between each of said blocks and its adjacent plate so as to urge them apart, and adjusting elements adapted selectively to space each of said blocks and their adjacent plates in relation to each other whereby the tension of said spring means upon its sliding block is regulated, said adjusting elements comprising an outer end portion of said housing and a pair of substantially horizontal adjusting screws extending through threaded bores in said end portion of said housing. said screws having inner ends bearing against said plate and having outer headed ends accessible outside said housing.

GEORGE R. DALE'.

6 REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,614,816 York Jan. 18, 1927 1,762,772 Fisher June 10, 1930 2,165,759 Nyborg July 11, 1939 2,243,538 Salfisberg May 27, 1941 2,413,339 Stadelman Dec. 31, 1946 

